This invention applies to plastic foam materials, and in particular to the materials used in manufacturing molded foam products having high insulation and cushioning capabilities, such as products for shipping boxes, including corrugated cardboard shipping containers used to store and ship fragile or perishable materials. Such foam insulation materials are widely used at present in the form of plastic foams that are made from petrochemicals. The principal disadvantages of such currently known manufacturing methods are that they require the use of petrochemical materials which are non-renewable resources and they employ environmentally-destructive chemicals as foam blowing agents. They also pose a substantial burden on solid waste disposal methods, are not bio-degradable and are not readily recyclable.
The present invention also relates to my co-pending patent application entitled: Process for Making Fiber Foam Packaging From Recycled Paper and Fiber Products, Ser. No. 562,833.
The basic purpose of the present invention is to provide foam plastic products for both impact and thermal insulation as well as structural purposes, made from materials which are renewable resources that are both recycled and recyclable.